Now to chant the magical incantation that will exorcise the System library
from LLVM forever:

grep -lR "llvm/System" * | grep -v .svn | xargs sed -ie 's#llvm/System#llvm/Support#g'

llvm-svn: 120314
diff --git a/llvm/lib/Support/Unix/Mutex.inc b/llvm/lib/Support/Unix/Mutex.inc
index 5c50697..fe6b170 100644
--- a/llvm/lib/Support/Unix/Mutex.inc
+++ b/llvm/lib/Support/Unix/Mutex.inc
@@ -1,4 +1,4 @@
-//===- llvm/System/Unix/Mutex.inc - Unix Mutex Implementation ---*- C++ -*-===//
+//===- llvm/Support/Unix/Mutex.inc - Unix Mutex Implementation ---*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //